Re: [PATCH v3 14/16] phy: Add notify_speed callback

[Manu Gautam <mgautam@codeaurora.org>]

Hi


On 12/20/2017 12:47 PM, Kishon Vijay Abraham I wrote:
> Hi,
>
[snip]
>>> Why not use a notification mechanism instead of adding new APIs in phy-core.
>>> This will only bloat phy-core with APIs for a particular platform.
>> Do you mean notifier_chains ?
>> When we have multiple instances of USB PHYs then notifier chains are not
>> of much help. For any platform glue or PHY driver it will be very difficult to
>> figure out if notification received for speed was for same phy/bus or a
>> different one.
>> Using PHY callbacks looked more elegant to me. Additionally PHY drivers
>> can also use this info decide power management policy e.g. if speed is
>> INVALID then it means PHY is not in a session and it can enter deepest
>> low power state.
>> Additionally if you prefer set_speed name over notify_speed then I am
>> ok with that as well so that it sounds more generic.
> I'd prefer adding modes in enum phy_mode according to speed and using phy_set_mode.

yeah, that also seems good idea. How about something like this:

--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -23,12 +23,16 @@
 struct phy;
 
 enum phy_mode {
-	PHY_MODE_INVALID,
-	PHY_MODE_USB_HOST,
-	PHY_MODE_USB_DEVICE,
-	PHY_MODE_USB_OTG,
-	PHY_MODE_SGMII,
-	PHY_MODE_10GKR,
+	PHY_MODE_INVALID	= 0,
+	PHY_MODE_USB_HOST	= BIT(0),
+	PHY_MODE_USB_DEVICE	= BIT(1),
+	PHY_MODE_USB_OTG,	= BIT(2),
+	PHY_MODE_SGMII		= BIT(3),
+	PHY_MODE_10GKR		= BIT(4),
+	PHY_MODE_USB_LS		= BIT(5),
+	PHY_MODE_USB_FS		= BIT(6),
+	PHY_MODE_USB_HS		= BIT(7),
+	PHY_MODE_USB_SS		= BIT(8),
 };


This way I don't need to duplicate USB speed enums for host/device or otg modes.

> Thanks
> Kishon

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